Apparatus for controlling combustion



Novi 17,1925. 1,562,338 V J. L. KIMBALL I APPARATUS FOR CONTROLLINGCOMBUSTION Filed Feb; 11, 192 2 Sheets-Sheet 1 [Ni/EN 7-0/2 Nov. 171925- ,338

J. L. KIMBALL APPARATUS FOR CONTROLLING COMBUSTION Filed Feb. 11, 1924 2Sheets-Sheet 2 [/v L/EN TOR Patented Nov. 17, 1925.

UNITED STATES PATENT OFFICE.

JAMES LEWIS KI EALL, 0E SALEM, MASSACHUSETTS, Assienon. ToRUGGLES-KLINGE- MANN MFG. 00., or SALEM, MASSACHUS TTS, A C RPOR TION OFMASSACHUSETTS.

APPARATUS FOR ooNTRoLLTNG-coMEUSTIoN.

Application filed February 11, 1924. Serial-No. 692,050. f

To all whom it may concern:

Be it known that I, JAMES LEWIS KIMBALL,

a citizen of the United States, residing at 9 Dearborn St, Salem, in thecounty ofEssex and State of Massachusetts, have invented certain new anduseful Improvements in Apparatus for'Gontrolling Combustion, of whichthe following is a specification.

This invention relates to apparatus for automatically controllingcombustion in a steam boiler furnace in accordance with variations insteam pressure generated by said boiler.

One of the objects of the invention is to provide independent regulatorsfor the control of uptake dampers of a plurality of steam boilers, saidregulators being actuated by mechanical means from a master regulatorwhich derives its motion from variations in pressure and which is usedto control the fuel feed.

Another object of the inve'ntionis to proride means in the control ofthe mechanically operated regulator whereby known variable factors inthe control will be compen-l sated for and thereby maintain apredetercontrolling air and fuel supply the fuel feed should becontrolled uniformly from load or pressure variations, while the airsupply should be controlled step by step, andat each stepped positionthe fuel controlling regulator should have a limited operation withouteffecting operation of the draft con-' trol regulator; In my inventionthe air control regulator is not responsive to small fluctuations in thefuel control regulator, the operation is intermittently effected bysteps each stage of operation requiring a predetermined degree ofoperation of the. fuel controlling regulator for smaller movements ofthe fuel control regulator the draft control reg l to is re p nsi e- .Inthis w y it will be seen that my invention'reduces Lie number ofdisturbances in the regulation of the furnace draft and therefore thefurn'a efficiency approaches more nearly to the efiiciency to be gainedby a fixed air supply. I

The invention'is arranged to be used in conjunction with any desiredtype of regulator in which its operation is controlled from pressure. IFor the purpose of illustrat ing my invention, I have shown in the accompanying drawings the regulator which is actuated from pressure ascontrolling thefuel feed, and my invention which is actuated bymechanical means as controlling the boiler damper. But, it should beunderstood r l that this is only a preferred arrangement and that thepressurefregulator could be' used'to control the damper if so desired,and my invention used to control the fuel feed, or any other arrangementof control" which under existing conditions seemed de-I sirable could beused without departing from the scope; of-niy invention.

The present day practice is to control both fuel feed and air; supplyfromo'ne regulator, but this gives a uniform movementto the.

damper'and the fuel feed from a uniform;

variationin pressure and does-not take into account the variable gasflow past the damper. Uniform pressure variation should produce auniform variation in'air supply and not a uniform damper movement. I Myinventionprovides powerful damper regulator with a variable' control'tocom-- pensate for these variable characteristics One orvmore of theseregulators being oper ated from a master regulator and the masterregulator being operated from either the pressure of. the steamgenerated by the boil or, so the pressure of gases generated in-thefurnace. 'In the accompanying drawings forming a part of thisspecification, Figure 1 is a; diagrammatic view showing a steam boilerwith fuel feeding mechanism and an engine for driving the fuel feeder,also a regulator t which is controlled in accordance with-the steamgenerated in the boiler for controlling. the speed of the Stoker engine.This regulator alsocontrolling the operation ofaregulator which controlsthe boiler damper. Figure 2 shows a vertical section of the damperregulator, a part being shown in section for a clearer understanding ofits operation.

Referring first to Figure 1, (1) designates an automatic stoker forfeeding fuel to the boiler furnace which maybe of any desired type. (2)designates an engine for driving the stoker. Engine (2) has steam supplypipe and throttling valve A regulator (5)has steam pressure connection(6), and operates to controlthrottling valve from variations in pressuregenerated by the boiler or boilers. This regulator can be of any desiredor conventional type, a preferred embodiment of a regulator suitable forcarryingout my invention being disclosed in my application, SerialNo.1(330,289, of April-6, 1928, but it should be understood that anyother type of regulator which is controlled from pressure and which.will effect a uniform variation in stoke r speed from a uniformvariation in pressure, will be suitable for carrying out this invention.

In the operation of this preferred regulator, the steam pressure acts ona flQXllJlG diaphragm (7) and this pressure is counteracted by weightsattached to beam (9).

Variations in steam pressure operate beam (9') to control a pilot valve(10) andpilot valve (10) controls an independent pressure supply itooperate fluid pressure motor (11). Fluid pressure motor .(11) has apiston operating in a cylinder connected to piston rod (12) and this rodis in turn connected by means of a cord or other connecting means withthrottling valve If a cord or cable connection is used :then acounterweight (13) is used to operate valve (4c) in one direction, whilethe regulator operates the valve in the other direction.

It should be understood that on an in crease in steam pressure pistonrod"(12) will operate in an upward direction to close throttling valveand likewise on a decrease in steam pressure piston rod (12) willoperate in a downward direction to open throttling valve While we haveexplained the operation of this regulator from steam pressure, it shouldbe understood that any regulator suitable for controlling stolzer speedfrom furnace pressure could be used without departing from the s' ope ofthis invention. Each individual boiler is provided with a damper havingdamper arm (15), and a counterweight (16) for closing the damper, andeach individual damper is provided with an individual regulator forcontrolling its respective damper by means of suitable connections 17)withthe-damper arm.

' I will now explain the novel features in the operation of thisinvention Referring to Figure 2, (18) designates a fluid pressure motorhaving piston (19) 039, of June 31st, 1922.

and piston rod (20), a pilot valve (21) controls an independent pressuresupply for operating piston (19), the inlet for pressure is at (22) andexhaust at This valve can be of any preferred arrangement in which theadmission and exhaust of fluid pressure will effect the operation of Vthe piston A suitable valve for this purpose is shown in my prior PatentNo. 1,l05,-

The pilot valve stem (2d) has cylindrical portions and which control theadmission and exhaust to opposite'ends of the motor cylinder (18), thestem being shown in a neutral position in which no water or other fluidpressure can be admitted orexhausted to or from the motor cylinder (18)when the stem (24 is raised, pressure is admitted at port (27) tooperate the piston (19 in an upward direction at the same time exhaustport (28) is opened to the atmosphere,allowing pressurezto es: ape fromthe top of the cylinder, and when the stem is lowered, the action isreversed, pressure being admitted at port (.528) and exhausted at port(27), and piston (19) is operated onthe down\ ard stroke.

lit should be explained that pressure exhausted from the top of the.motor cylinder is discharged into the bottom cavity of the pilot valvewhere it is discharged through a cored passage not shown tothe topcavity of the valve and water goes to waste through exhaust connection(23;);

From the foregoing it will be seen that an upward movement of the valvestem will operate the piston (19) and piston rod in an upward direction,and likewise a downward movement of the stem (24) will operate piston(19) andpistonrod (20).

in a downward direction. The valvespindle (2a) is operated by movementsof a beam (29) through yoke connections (30) and (31) to floating leverFloating lever is pivoted to the beam (29.) at point (33). The left handend (34) being held stationary while the beam is moving the valve stem(24c) to either an upper or lower pressure position. The beam (29) ispivoted at point the opposite end being moveable by means of a cam Thiscam derives its motion for operating the beam (29) by means of cable (37which extends around pulley (38), pulley (38) being secured to cam shaft(89) and operates the mini-(36) in one direction by the counter-weight(4:0), and in the other direction by the travel of piston rod .(12)of-the pressure regulator (5) Yf-t is understood that I do not limitmyself to the described details of operating the pilot valve of thedamper regulator from, the operation of the piston rod of the regulaterthat is actuated from variations in steam or other pressure and that thedescribed details of construction might be ill) modified in various wayswithout departing fromothe spirit of this invention. i

WVe will now show how my novel com pensating attachment which isoperatedfrom the piston rod effects a variable cut-oft giving a variablecontrol over the movement of the piston (19) from uni-. form motionimparted to the cam (36) and thereby governs the movement of the damp- Iers in such a way as to effect a uniform air there-fore, what isrequired is a variable movement to the damper from a uniform pressurevariation to compensate for the variable gas flow past such dampers.

It should also be understood that the conditions of the gas flow ordraft varies in different boilers of the same generating systen'i. Thoseboilerslnearest the. main stack or chimney usually getting a greaterdraft .thanjthose located at the extreme ends of the-battery. It is forthis reason that all dampers must not'only have a variable movement inrelation to the fuel feed, but the individual damper should beprovidedwith a variable movement in relation to other dampers. A uniformvariation in fuel feed and a uniform variation in gas flow for eachindividual boiler, from a un form pressure varlat on of the stean'i,generated by all the boilers, 1s what 1s re quired.

this bar are upper and-lower slotted arms (43) and (44). Screw studs(45) and"(46)'1 are clamped in the slotted ends of arms (43) A flexiblesteel blade (4T)-has- (45) and itsv and (44). its upper end attached tostud lower endto stud (46).

It will be seen that the moved in or out in the slotted ends of thesearms.

being shown, the rod being broken and other arms left'oif for thepurpose of clearness in showing the connection backofthis compensatingattachment. These named arms: are arranged .to be, ad usted verticallyin relation to each other, and have,

studs arranged to be adjusted in and out in theslotted ends of theseadjustable arms (49). Studs (50)are ofsimilar con v I bled? ill impartmotion to reel cnmpen-.,

structi n to studs (45) anagae e e t that l lttflCllGd-tO piston rod atpoint (41) is a bar (42) which moves up and down with the piston rod(20), and attached to.

angle of this flexi ble blade can be varied by the studs 'beingg v Theseupper and lower arms also.

carry'rod (48) .to which is clamped otherarms (49) of similarconstruction, only one lastthey are notafaste'ned ito the flexibleblade, but simply act as a, guide {for the-blade. It will be seen thatthis flexiblesteel blade;

can be clan'iped so as to form any curve re quired within the limits of"adjustment of thestuds Floating lever.

pensating lever hasa pivoted'bearing at point (54) the .vbracket forthis bearing/be ing supported by the frame of the regulator, The righthand end of compensating lever (51) ,is'

but not shown in the drawing.

connectedwith the beam (29))by means of.

a spiral spring (55),. arm- (56) -is' secured to lever (51) and has roll(57) at its up-f. per, end. Roll-(57) is held in engagementwith theflexible blade (47) Hby means of spring (55).

In the operation of this regulatorpvaria-i is t apatit- (34) ravithcompensatin level, by means of links nd v'l his com:

tions in the movement of the piston rod. (12) of pressure regulator (5)will operate cam (36)., an upward moi ement effecting an upward movementofbeam. (291), and an upward movement of; the pilot valve stem (24)Ywhich in turn will effect an upward:

movement of -pis'toni;(19). -These upward motions of the two regulatorsare in the direction toslowdownthe 'stolier engine.. and-close the fluevdamper. fLikewise. -a= downward ,movement of piston'. rod i caused bydecrease in steam pressure will effect a;speeding;up ofthe-stOkeiiengineand likewise downward movem'entiof rod (20) to open the fl uedampeipipiston Referring to 'Figurellii, it-Jwill be semi that whenthe beam(29);;is raised by means of cam (86), that the pilot valve stem (24)will be moved to afpressure position which will admit water at port-(27)-and open port (28) to exhaust, this will operate."pis v ton (19)Iin an upward direction; {The movement of the, piston (119) will causea;

similar motion to be imparted to the flex-- ibleblade. (47) andthi'smotion willcon-f.

tinueuntil the-'roll v (57 comes :in contact with one of the studs-(50)and this will? i give *arocking'motion to lever (51)'- and: floatinglever ,(32) whichgwill return the:

pilot, valvestem (24) touits neutral enmeoif position.

There will begsomemcompensating effect imparted-to the valve between thelocation of the studs'bythe curvature of the flexible blade (47),butthese studs will effect an abrupt closing of the, valve toprevent afurther movement of the pis ton rod (20). Assuming a. downward move-1ment of piston rod;f(12), n a d a ii steam pressure, 'cami(36): willoperate beam.

(29) to lower valve stem: ('24), and admit,

pressure at port (28) andopen port.;(27)

to exhaust which willoperate'piston'.(19):;, on the downward stroke andthe. flexible 1-3 1 plete stroke without cut-off eiiect.

sating arm (51) and floating lever ('32) to again return the pilot valvestem to a neutral or cut-off position.

- From the foregoing, it will be seen that the movement of thecam (36)will move the pilot valve stem (24) to either one or the other of itspressure positions for operating the piston (19), and the operation ofthe piston through the action of the compensat- 1 ing attachment will ineach case return the effect the necessary cut-off motion. These studssimply act to give an abrupt motion to the cut-off mechanism so' as toobtain step actlon.

It will be seen that the flexible blade can be formed into any desiredcurve to give the necessary variable control over the movement of pistonrod (20) 'inrelation to the movement of piston rod It will be seen thatthis blade can be adjusted to a vertical line for a given distancecorresponding to the necessary closing movement of the damper to obtaina grip on the draft. This means that there will be no cut-"o'fl orcompensating effectup to' this point, and I from this point on the bladecan be so adjusted as to efiect a uniform variation in gas flow for auniform variation in Stoker speed.

vOne of the valuable "features of this in-' vention is to be able toapply a damper regulator to control each independent damper in aplurality of boilers, and to so control eachdamper in relation to theregulator which is controlled by the pressure as to compensate forvariable gas flow from the furnace of theindividual boiler.

The foregoing specifications With the accompanying drawings arepresented for the purpose of describing and illustrating the broadprinciples of this invention, and I desire to have it understood thattheinvention is not to be restricted by reason-of the specific constructionor application disclo'sec or otherwise than as by the claims.

Having thus described my invention,

'* what I claim as new and desire to secure by Letters Patent, is I pI 1. In a regulator comprising a reversible motor and an operatingelement for controlling said motor, a cam member for actuating saidoperating element, and an adjust able compensator operated by said motorcoacting with said cam whereby the operating element is jointlycontrolled by saidcam and by the operation of said motor to effect avariable step by step control of said motor,

2. In combination with a regulator controlled from fluid pressure, asecond regulator comprising of a reversible motor and an operatingelement for controlling a source of power to actuate said motor, meanscontrolled by the first named regulator to operate the operatingelement, and an adjustablecompensator operated by said motor co-actingwith said means whereby the operating element is controlled jointly bythe first named regulator and by the motor to effect a variable step bystep 'control of said motor.

In apparatus for controlling combustion in a boiler furnace, in;combination a regulator controlled in accordance with variations inpressure, a second regulator having a reversible motor and an operatingelement for controlling said motor, means operated by the first namedregulator for operating the operating element for controlling a sourceof power to operate said motor, and means operated by the motor foreiiecting a variable control of said regulator in relation to the firstnamed regulator.

4. I11 a pressure system, means to regulate the pressure in the systemcomprising a regulator controlled from variations of pressure in thesaid system, a second regu lator having a reversible motor and anoperating element for controlling a source of power to operate saidmotor, means operated by the first namedregulator for operating theoperatingelement and means operated by the motor co-acting with saidmeans to effect a variable control of said regulator in relation to themovement of the first named regulator.

5. In apparatus for controlling combustion in a boiler furnace, incombination a regulator controlled in accordance with variations inpressure, a second regulator having.

reversible motor and operating element for controlling said motor,mechanical, means operated by the first named regulator for operatingthe operating element to control a source of power to operate the motor,and compensating means operated by the motor for effecting theincremental control of said regulator.

6. In a system for controlling fuel feed nace's comprising a separatereversible motor for controlling the air controlling means of eachboiler furnace, said motors having an operating element for controllingthe motor and its direction of operation, a master regulator forcontrolling the fuel feed and the operating elements of said motorssimultaneously, said master regulator "being c'on trolled by variationsin pressure generated by all of said boilers, an ad'ustable 'compensatoroperated by each of said motors co-acting with the operating elementwhereby the motors are controlled in abrupt steps of varying amounts,whereby the air controlling means is variably controlled to compensatefor variable factors between the fuel feed and air supply.

7. In combination with a regulator controlled from fluid pressure, asecond regulator comprising a reversible motor and an operating elementfor controlling a source of power to operate said motor, said operatingelement having a neutral position in which it is not effective foroperating the motor and two effective positions for operating the motorand for controlling its direction of operation, means operated by thefirst named regulator for operating the operating element to either ofits effective positions, and means operated by the motor I motor, saidoperating element having a neutral position in which the motor is notelfective, and two effective positions for operating the motor, andcontrolling its direction of operation, remote control means .foruniformly operating the operating .ele-

ment to either of its effective positions, and

variable control means operated by the mo 7 tor co-acting with saiduniform control means whereby the motor is variably controlled inrelation to the motor control means.

JAMES LEWIS KIMBALL.

